QuakeIndex

Earthquake · reviewed by a seismologist

M 2.7ml

17 km WNW of Chignik Lake, Alaska

· 2.7 km deep · released about 340 lb of TNT

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Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 2.7 (ml)
Depth
2.7 km below the surface
Felt
no reports yet
Measured shaking
intensity II (ShakeMap)
USGS impact alert
green
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 1137 days ago

This was a small earthquake. Shaking like this is often felt indoors nearby and very rarely causes damage.

How big was it?

This earthquake released about 340 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 3.7 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 45,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 32,000× the energy of this one
  3. Around the size people start to feel M 3.0 2.8× the energy of this one
  4. This earthquake M 2.7 about 340 lb of TNT

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

Where

Epicentre 56.3108, -159.0215. Map © OpenStreetMap contributors.

Aftershocks so far

56 earthquakes have been recorded within 50 km since this one.

  1. 2.3 23 km N of Ivanof Bay, Alaska
  2. 1.9 5 km E of Chignik Lake, Alaska
  3. 1.8 34 km SSW of Port Heiden, Alaska
  4. 2.7 33 km W of Chignik Lake, Alaska
  5. 1.9 21 km SSE of Chignik Lake, Alaska
  6. 2.5 5 km SW of Perryville, Alaska
  7. 1.5 20 km SSW of Chignik Lake, Alaska
  8. 1.9 19 km WNW of Chignik Lake, Alaska
  9. 2.3 40 km NW of Chignik Lake, Alaska
  10. 1.7 27 km NNW of Chignik Lake, Alaska
  11. 2.5 17 km WNW of Chignik Lake, Alaska
  12. 2.5 55 km SW of Port Heiden, Alaska
  13. 3.7 35 km SSE of Chignik Lake, Alaska
  14. 1.5 32 km N of Chignik Lagoon, Alaska
  15. 1.7 14 km N of Chignik Lagoon, Alaska

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.